Some readers may recall building a line-following robot during their school days. Involving some IR LEDs, perhaps a bit of LEGO, and plenty of trial-and-error, it was fun on a tiny scale. Now imagine that—but rideable. That’s exactly what [Austin Blake] did, scaling up a classroom robotics staple into a full-size vehicle you can actually sit on.
The robot uses a whopping 32 IR sensors to follow a black line across a concrete workshop floor, adjusting its path using a steering motor salvaged from a power wheelchair. An Arduino Mega Pro Mini handles the logic, sending PWM signals to a DIY servo. The chassis consists of a modified Crazy Cart, selected for its absurdly tight turning radius. With each prototype iteration, [Blake] improved sensor precision and motor control, turning a bumpy ride into a smooth glide.
The IR sensor array, which on the palm-sized vehicle consisted of just a handful of components, evolved into a PCB-backed bar nearly 0.5 meters wide. Potentiometer tuning was a fiddly affair, but worth it. Crashes? Sure. But the kind that makes you grin like your teenage self. If it looks like fun, you could either build one yourself, or upgrade a similar LEGO project. Continue reading “Honey, I Blew Up The Line Follower Robot”→
One of the most basic problems with robotic arms and similar systems is keeping the weight down, as more weight requires a more rigid frame and stronger actuators. Cable-driven systems are a classic solution, and a team of researchers from MIT and Zhejiang University recently shared some techniques for designing fully 3D printed cable-driven mechanisms.
The researchers developed a set of four primitive motion components: a bending component, a coil, screw-like, and a compressive component. These components can work together in series or parallel to make much more complicated structures. To demonstrate, the researchers designed a gripping tentacle, a bird’s claw, and a lizard-like walking robot, but much more complicated structures are certainly possible. Additionally, since the cable itself is printed, it can have extra features, such as a one-way ratcheting mechanism or bumps for haptic feedback.
These printed cables are the most novel aspect of the project, and required significant fine-tuning to work properly. To have an advantage over manually-assembled cable-driven systems, they needed to be print-in-place. This required special printer settings to avoid delamination between layers of the cable, cables sticking to other components, or cables getting stuck in the mechanism’s joints. After some experiments, the researchers found that nylon filament gives the best balance between cable strength and flexibility, while not adhering tightly to the PLA structure.
One might be tempted to think that re-creating a film robot from the 1950s would be easy given all the tools and technology available to the modern hobbyist, but as [Mike Ogrinz]’s quest to re-create Robby the Robot shows us, there is a lot moving around inside that domed head, and requires careful and clever work.
The “dome gyros” are just one of the complex assemblies, improved over the original design with the addition of things like bearings.
Just as one example, topping Robby’s head is a mechanical assembly known as the dome gyros. It looks simple, but as the video (embedded below) shows, re-creating it involves a load of moving parts and looks like a fantastic amount of work has gone into it. At least bearings are inexpensive and common nowadays, and not having to meet film deadlines also means one can afford to design things in a way that allows for easier disassembly and maintenance.
Robby the Robot first appeared in the 1956 film Forbidden Planet and went on to appear in other movies and television programs. Robby went up for auction in 2017 and luckily [Mike] was able to take tons of reference photos. Combined with other enthusiasts’ efforts, his replica is shaping up nicely.
We’ve seen [Mike]’s work before when he shared his radioactive Night Blossoms which will glow for decades to come. His work on Robby looks amazing, and we can’t wait to see how it progresses.
[Tazer] built a small desktop-sized robotic arm, and it was more or less functional. However, he wanted to improve its ability to pick things up, and attaching a pneumatic gripper seemed like the perfect way to achieve that. Thus began the build!
The concept of [Tazer]’s pneumatic gripper is simple enough. When the pliable silicone gripper is filled with air, the back half is free to expand, while the inner section is limited in its expansion thanks to fabric included in the structure. This causes the gripper to deform in such a way that it folds around as it fills with air, which lets it pick up objects. [Tazer] designed the gripper so that that could be cast in silicone using 3D printed molds. It’s paired with a 3D printed manifold which delivers air to open and close the gripper as needed. Mounted on the end of [Tazer]’s robotic arm, it’s capable of lifting small objects quite well.
China played host to what, presumably, was the world’s first robot and human half-marathon. You can check out the action and the Tiangong Ultra robot that won in the video below. The event took place in Beijing and spanned 21.1 km. There was, however, a barrier between lanes for humans and machines.
The human rules were the same as you’d expect, but the robots did need a few concessions, such as battery swap stops. The winning ‘bot crossed the finish line in just over 160 minutes. However, there were awards for endurance, gait design, and design innovation.
How far can you stretch a measuring tape before it buckles? The answer probably depends more on the tape than the user, but it does show how sturdy the coiled spring steel rulers can be. [Gengzhi He et. al.] may have been playing that game in the lab at UC San Diego when they hit upon the idea for a new kind of low-cost robotic gripper.
Four motors, four strips of measuring tape (doubled up)– one robot hand.
With the lovely backronym “GRIP-tape” — standing for Grasping and Rolling in Plane — you get a sense for what this effector can do. Its two “fingers” are each made of loops of doubled-up measuring tape bound together with what looks suspiciously like duck tape. With four motors total, the fingers can be lengthened or shortened by spooling the tape, allowing a reaching motion, pivot closer or further apart for grasping, and move-in-place like conveyor belts, rotating the object in their grasp.
The combination means it can reach out, grab a light bulb, and screw it into a socket. Or open and decant a jar of spices. Another video shows the gripper reaching out to pick a lemon, and gently twist it off the tree. It’s quite a performance for a device with such modest components.
At the moment, the gripper is controlled via remote; the researchers plan on adding sensors and AI autonomous control. Read all the details in the preprint, or check below the fold to watch the robot in action.
[Charmed Labs] are responsible for bringing numerous open-source hardware products to fruition over the years, and their latest device is an adorably small robotic camera platform called Goby, currently crowdfunding for its initial release. Goby has a few really clever design features and delivers a capable (and hackable) platform for under 100 USD.
Goby embraces its small size, delivering what its creators dub “tinypresence” — or the feeling of being there, but on a very small scale. Cardboard courses, LEGO arenas, or even tabletop gaming scenery hits different when experienced from a first-person perspective. Goby is entirely reprogrammable with nothing more than a USB cable and the Arduino IDE, while costing less than most Arduino starter kits.
Recharging happens by driving over the charger, then pivoting down so the connectors (the little blunt vampire fangs under and to each side of the camera) come into contact with the charger.
One of the physical features we really like is the tail-like articulated caster at the rear. Flexing this pivots Goby up or down (and can even flip Goby completely over), allowing one to pan and tilt the view without needing to mount the camera on a gimbal. It also comes into play for recharging; Goby simply moves over the disc-shaped charger and pivots down to make contact.
At Goby‘s heart is an ESP32-S3 and OmniVision OV2640 camera sensor streaming a live video feed (and driving controls) with WebRTC. Fitting the WebRTC stack onto an ESP32 wasn’t easy, but opens up possibilities beyond just media streaming.
Goby is set up to make launching an encrypted connection as easy as sharing a URL or scanning a QR code. The link is negotiated between bot and client with the initial help of an external server, and once a peer-to-peer connection is established, the server’s job is done and it is out of the picture. [Charmed Labs]’s code for this functionality — named BitBang — is in beta and destined for an open release as well. While BitBang is being used here to make it effortless to access Goby remotely, it’s more broadly intended to make web access for any ESP32-based device easier to implement.
As far as tiny remote camera platforms go, it might not be as small as rebuilding a Hot Wheels car into a micro RC platform, but it’s definitely more accessible and probably cheaper, to boot. Check it out at the Kickstarter (see the first link in this post) and watch it in action in the video, embedded just below the page break.